Centrifugal casting machine



I May4,1926.'

J. w. COBURN CENTRIFUGAL CASTING MACHINE Filed Jan. :56. 1920 :5 Sheets Sheet 1 INVENTOR JcQW/(JI/ f 0160/ o o W r.

I ATTORNEY May 4 1926.

J. w. COBURN CENTRIFUGAL CASTING MACHINE Filed Jab. 30. 1920 s Sheets-Sheet 2 Y I INVENTOR final/ abuzz ATTORNEY May 4 .1926.

3 Sheets-Sheet 5 0% N W i m w m-x-w W Z& W

INVENTOR Ja'ms l/flabahv ATTORNEY Patented May 4, 1926.

UNITED STATES PATENT. 0mm,

nuns w. corona", or HIGHLAND rank, mrcmem, assrenon or o m-roun'rn '10 enannns n. wrsnnn, or nnrnorr, mzccmean.

GENTBTFUGAL CASTING MACHINE.

' Application filed January 30, 1920. Serial No. 355,287.

To all whom it may concern:

Be it known that I, JAMES W. 0013mm, a

citizen of the United States, residing at Highland Park, county of Wayne, State of Michigan, have invented a certain new and useful Improvement in Centrifugal Casting Machines, and. declare the following to be a full, clear, and exact description of the same, such as will enable others skilled in the art to which-it'pertains to make and use the.

same, reference bein had to the accom anyin'g drawings, whic 1 form a part 0 this specification.

This invention relates to centrifugal casting machines, and its object is to providean ap aratus and method for. casting metal artic es in a metal mold by centrifugal action, the form of the article being accurately determined by the mold. A further object is to provide an a paratus and method of casting metal artic es by centrifugal force in a rotatable mold member into. which molten metal in excess of that required to form the article may be delivered and the excess metal discharged from the mold box, an article of the desired size and -thickness'of wall being accurately determined by the character of the mold. An additional object of the"in' vention is to provide a centrifugal casting machine having a rotatable mold box providedwith a plurality of peripheral mold cavities positioned about the exterior of the box and open to thehollow interior within which the molten metal is to be deposited. Thus, also, the object of the invention is to provide a process and mechanism whereby a quantity'of molten metal may be deposited in the box and made to flow by force imparted to the mass intothe mold cavity or plurality of cavities through achan-nel open to atmosphere. Other novel features of the invention reside in the mechanism employed for the casting of cylindrical articles of' specified width of the wall and in the con struction of the mold itself having a plurality of cavities open to -the common hollow; interior and in the mechanlsmv for control casting machine constructed according to my invention.v p

Fig. 2 is a section taken on line 2--2 of Fig. 1 showing one form'of mold box.

Fig. 3 is a plan View showing a different type of mold box.

Fig. 4 is a section thereof taken'on line 4-4 of Fig. 3.

Fig. 5 is a plan view of the portion of a mold box showing a different type of mold .cavity. C

Fig; 6 is a section taken. on line 6--6 of Fig. 5.

a The apparatus consists of ahead or cage 1 containing the mold box which is adapted to be positioned at an angle to the Vertical as will be understood from Fig. 1. This member 1 is mounted on arms 2 secured to a cas ing 3 which casing is fastened to a flange 4 and adapted to be positioned at various angles to the vertical by means of bolts 5 of roller bearings 11 and 12 at opposite ends and the shaft 9 is supported by similar bearings 13 within the-casing 10. On the shaft 9 is one member 14 of a cone clutch and this member has a sprocket 15thereon and further is loosely mounted on the shaft 9.

The companion clutch member 10 is splined to the shaft 9 and a spring 17 is provided to force the clutch member 16 into engagement 1 with its companion 14. A weighted rock gaging a ring 19 provided in the circumferen'tial groove on the clutch member I 16 and the rocking of the lever toward the left of lever 18 also has an arm 20 extending to and beneath the shoe 21 on the pivoted control lever 22.. This shoe 23 as nay be understood from Fig. 1 may be made todepress the end 20 of the lever to disengage the clutches and, by releasemf the lever, the spline 171 and weighted end ofthe lever 18 act to ring the clutch members into engagement.

' The gear 15 is to-loe understood as being Fig. 2 disengages'the clutch members. This lever 18 is providedhavi-ng a forked arm en- I connected by what is known as a silent chain with a similargear on the drive shaft 24 of the motor indicated at 25, the chain being enclosed within a casing 26 extendlng between the shafts 9 and 24. With the clutch members in engagement, as shown in Fig. 2, the motor rotates the shaft 6 which revolves the head 30 secured thereto. and to this head is secured the box 31 containing the mold 32.

As is hereinafter more fully shown the mold member may be of various types. In the case shown in Fig. 2 the mold 32 is cylindrical in form closed at the lower end and open at the upper end fitting within the recess in the box 31. A cover member 33 is provided for this mold having a central aperture 34 less in diameter than the internal diameter of the mold 32 and the extent to which the cover member 34 projects over the open upper end of the mold 32 determines the thickness of the wall of the cast cylinder. In operation the molten metal is poured through the aperture 34 into the mold member during revolution of the mold.

or even prior to revolution thereof and the mold immediately whirled. Centrifugal at? tion forces the metal to the periphery of the mold and due to the high speed of revolution (which is about 1500 revolutions per minute) the material in excess of that required to formthe thickness of the wall flows out throughthe aperture 34. By this method of forcing the metal to the circumference of the mold the lighter material or slag which may be poured into the mold with the metal will be discharged through the aperture 34 in the cover and thus the cast metal will be of uniform density and character, the centrifugal force compacting the particles and producing an article more dense in character than with the usual method of casting in a sand mold. Furthermore, no voids are possible in this method of casting as the gases will be discharged through thecentral orifice and the article will be uniform texture throughout.

The pover'33 is loose on the box 31 which is formed to receive flanges 35 on [the cover and the weighted levers 36 are pivotally mounted on the box 31 each having an end 37 engaging over the flange 35. These weighted levers, due to the centrifugal force securely hold the mold box in place during the castin ,operation but, upon cessation of rotation o the mold box, the weighted levers automatically release the cover and permit its ready removal. Hinged covers for this purpose have been found impracticable due to the great force applied thereagainstduring the casting operation but, by use of the weighted lovers, the, greater the centrifugal force applied, the greater the pressure will these levers exert to hold the cover in position and yet bythis construction acover that is freely and readily removable upon cessation of operation is secured. The head or cage 1 has an annular channel 38 provided thereabout on which is placed a cover 39 having a central aperture 40 and an additional cover 41 thereon which in turn has a central aperture 42 through which the metal may be introduced into the mold and all material that is discharged through the orifice- -34 of the cover 33 for the mold is, by centrifugal force, thrown outward into the channel 38 and after a period of time the metal in this chamber may be removed by removing the cover member 39.

Various types of castings may be made in the mold above described as for instance bearings, piston ring pots and various other cylindrical. objects and, while I am aware that cylindrical objects have been made by whirling a mold, the new features of this invention as regards, the casting of a cylindrical object is found in the provision of centrifugally operated levers for holding the cover in position and in the provision of a cover projecting over the open end of the mold to determine the thickness of the cyl inder to be cast and permitting the introduction of an excess amount of metal over that required to form the article for? which the mold is designed. A new feature'is here also involved in that provision is made to per mit introduction of excess material and subsequent discharge of'the excess and the provision of the receptacle for the discharged inner surface of the cast article and in the subsequent machining operations defects will be found but by this method above de-" scribed and introduction of an in leterminate quantity of the molten fluid in excess of that required enables the dross and slag to be discharged as such material is of lighter weight the conditions stated in which the metal is driven to the periphery of the mold the resultant article is of uniform character both on the inner and outer surface.

-So far as I 'am aware machinesfor casting articles by centrifugalforce have heretofore been utilized in the casting of a cylindrical article somewhat after the manner heretofore described. I have in practice,

however, found that, by the proper design and construction of the mold supported on the revolving head, articles of various shapes and of peculiar and nonunlform section may be cast as readily as cylindrical than the'metal itself and, therefore, under articles and this is accomplished by use of a mold of the character shown in Fig. 4.

of the mold has corresponding depressionsv therein as will be understood from Fig. 4

with these depressions '43..

registering 'With the two mold members 80 and 81 secured together as shown in Fig. 4, a mold cavity of the desired shape and character is provided between thesetwo members and at a distance from-the centerof the said members. The member 81 has a truncated ho'llow cone shaped portion 44 at the centerproviding an opening through which molten metal may be introduced into the hollow of the mold. These complemental mold cavities in the two members open to this central hollow cavity within the portion 44 and, upon introduction of metal into the cavity 45 and subsequent rotation of the mold, the metal is driven outward by centrifugal force into the mold cavities and in this case as in the former case the heaviermetal is driven to the periphery and the dross and lighter weight material remain in the. center. With this shape of'throat 'material has cooled.

or portion over the bottomof the mold, the flow of excess material from the mold is retarded insuring the filling of the cavities. The portion 44 may be made cylindrical in form in which case a more rapid discharge of excess material will result. With the curved type of cavity the cast articles will be found .connected together by a thin center web from which they may be readilv broken after the g In the case described the mold cavities are shaped to provide the ends of forked arms but any other shape maybe as readily provided as for instance as 'is' shown in Fig. 6 where the cavities are provided of a shape to form valve heads as will be understood from the 'cross section Fig. 6. In this case the mold cavity may be formed practically wholly .within the mold member 51 and, if so made,this mold member should have channels 52 leading from the hollow center of the mold to each cavity or the cavities may be formed partially within both members of the mold as in the case shown in Fig. 4. In this latter case as m the other case the heavier material 1s impacted llllO the'cavlties and, due

, to the centrifugal force compacting the material therein all voids are cllmlnated' as the gas escapes through the inlet to the cavities 43 to the center of the mold and passes out through the aperture provided in 44 which exten(ls ,jat an angle the upper portion and, if any material left in the mold, the lighter weight material will be in the web connecting the several cast articles.

In the type of mold shown in Fig. 4, the two parts are held together by the weighted levers 60 which are pivoted to a ring 61 engaging the periphery of the member 41 with the points 62 of the levers engaging in a groove in the support 63 for the said mold members which is attached to the shaft 6. The mold. members as shown in Fig. 4, are held withthe mold cavities in registration by 'means of the usual dowel pins 1n one of the elements fitting apertures in the other and the said levers 60 pivoted on the ring 1 v61 prevent separation of the two parts of the mold by centrifugal force andyet when the mold has ceased rotation the removable the mold a brake membe'r 70 is provided.

which has a shaft 71 attached thereto against which the coiled. spring 72 engages forcing the same to the left of the position shown .in Fig. 2. Upon moving the clutch member 16 backward the face of the brake member 71 is engaged thereby causing a frictional resistance to rotation of the clutch member and thereby causing cessation of rotation of the mold.

As heretofore stated, the head-1 carrying led the .mold' member and the shaft 6 for r'otating the mold are positionedat an angle to the vertical as shown clearly in Fig. 1. [he opening to the' mold is therefore of ready access and. the excess of-molten metal is readily into the receiver provided therefor.

1 Having thus fully described my inven tion, what I claim and desire to secure by Letters Patent of the United States is- 1. In acentrifugal casting machine, a revolublemold of hollow, cylindrical form having, integral side and bottom walls and an open upper end, a removable cover therefor having a central opening of a diameter less than the distance across the mold, the rotation of the mold discharging excess material through the central'opening, the thickness of the metal retained in the mold being determined by the distance to which" the cover extends over the mouth of the mold.

2.- In a ce ntr-ifngal casting machine, 'a revoluble mold having an open end, a cover therefor having acentral opening of a diameter less than the open end of the mold for retaining material in the mold. centrifugally discharged by centrifugal action operated means for iolding the cover in the inner wall positioned about the cover 1n position to receive excess material discharged through the opening of the cover by centrifugal force.

3. In a centrifugal casting machine, a revoluble mold having an open end, the longitudinal axis of which is at'an angle to'the vertical, a cover therefor having a central opening ofa diameter less than the diameter of the open end pf the mold, pivotally supported, weighted, levers actuated bycen-, trifugal force during revolution of the mold for retaining the cover thereon, and means for positioning the mold with the longitudinal axis thereof at various angles from a vertical to nearly a horizontal position.

4. In a centrifugal casting machine, a revoluble mold member, a shaft on which the moldis supported, a casing provided with a bearing for the shaft, a bevel gear on the shaft, a driving shaft, a bevel gear thereon meshing with the mold shaft gear, a frameor casing provided with bearings for the driving shaft, the mold shaft casing being attachable to the driving shaft frame and adapted to be adjusted in position thereon about an axis coinciding with the longitudinal axis of the driving shaft.

1 5. In a centrifugal vcasting machine, a revoluble mold member having an open, end, the longitudinal axis ofwhichis 'at an angle to the vertical, the mold caVity bemgsub-J stantially cylindrical in form, a cover for the said open end-having a centralfopning p of a diameter'less than the diameter; of the said end, the portion ofthe cover projecting Over the mold e g" he thickness of the wall of the cast body, and receiver f material discharged through the central opening positioned circumferentially about the cover and into-Which excess material is discharged by centrifugal force. I

6. In .a centrifugal casting machine, a revoluble mold, a shaft for rotating the same, he axis of rotation of the shaft and mold being at an angle to the vertical,v a driving shaft therefor, a clutch memben loosely mounted on the shaft, means for rotating the said member, a clutch member splined to the shaft, and means for withdrawing the said splined member from engagement with its companion, and a brake device adapted to be engaged by the splined member upon its withdrawal to cause cessation of rotation of the mold.

7." In a centrifugal casting machine in combination, a rotatable shaft, driving means therefor, a housing for the shaft. of

' a character to permit adjustment of the shaft at various angles relative to the-vertical a head on the said shaft, a mold member sup ported by the. head consisting of two parts providing a 'hollow interior, a series of mold cavltles coi'nple'mental portlonsv of which are formed in the meeting faces of the two parts, said head being of a character to receive and support one ofthe said parts and having a lateral flange extending about the periphery of both the said parts in a manner to hold the same in axial alignment, a retaining member for the second part, pivotally mounted weighted levers attached'to the retainer and having a portion adapted to engage the said flange of the head to clamp t e mold parts together by centrifugal action.

8. In a centrifugal casting machine, an 'open hollow, revoluble mold member having the longitudinal axis thereof at an angle to the vertical, the mold member being formed of two separable parts, there being a series of mold cavities complemental parts of 9. In centrifugal casting machine, a revoluble mold having a hollow interior and be 'ing positioned with the axis of revolution at an angle to the vertical, acover member therefor, centrifugally operated means for retaining the cover in position, the cover having a central aperture less in diameter than the open end of the mold, and a cylindrical receiver member about the periphery of the mold adapted to receive material dis- Telia ed through the cover aperture.

n a centrifugal casting machine, a ember, a. driving shaft, said frame having a housing for the driving en at ione'endthrough which the "'ects} and also havingg a;v lateral flange adjacent said open end,'a gear. on the said end of the driving-shaft, a driven shaft, -a gear thereon meshing with the driving shaft gear, a housing for the driven shaft,

said housing having an opening through which the drivingshaft extendsand being provided with a part complemental'to the flange of the driving shaft housing, means for fixedly attaching the riven shaft housing to the flange of the driving shaft housing, the arrangemeht permitting the positioningof the driven shaft at various angles relative to the vertical, and a revoluble mold me1nber carrid on the upper end of the driven shaft.

11. In a centrifugal casting machine, a revoluble mold member formed of two separable parts, the meeting faces thereof hav ing a series of mold cavities formed therein, the planeof the meeting faces being substantially at a right angle to the longitu dinalaxis of the .mold and the outer mold having a hollow central open ended portion for introduction of metal, a shaft to which the inner moldi'n'ember is; attached adjustable at an angle to the vertical, and cen-- T parts of the' moldtogether during rerolution thereof. a

' driving 'shaft, the mold shaft frame and driving of'the wallof the casting, said cover having -shaft frame being adapted to be secured together in fixed-relation to maintain the mold shaft and frame at any one of a'number of positions aboutthe axis of the driving shaft.

' 13. In a centrifugal casting machine, a-

revoluhle mold member having an open upper end intowhich molten metal may be introduced and from which excess material may be discharged by revolution of the mold, the mold member having an open end through which molten material may be introduced, a removable cover member having a central aperture less in diameter than the diameter of the mold defining the thickness a flange, a' series of'weighted levers pivot.-

ally supported on'thehousing having parts adapted to engage the flange and providing the sole means for retaining the cover in positionon the mold.

14. .In a centrifugal casting machine, a revoluble mold member having an open upper end, a removable cover therefor having a central opening of less diameter than the said open'end of the mold and through which molten metal may be introduced and excess .molten material discharged by centrifugal action, a stationary support, and a receiver detachably secured to the support into which excess material is finally discharged.

15. In a centrifugzl casting machine, a revoluble mold mem r having an open upper end through which molten metal may be introduced and through which material may be discharged byvrevo ution of the mold, a receivermember encircling the mold and of an inner diameter greater than the mold, said receiver member having an inner eripheral opening through which material harged om the mo d may enter the receiver, and a detachable cover for thereceiver.

16. In centrifugal casting machine, a revoluble mold member having an open upper end through which material may be mtroducedjand through which excess molten material may be discharged by revolution of the mold, a stationary receiver member of circular form consistirn 'of two detachable parts spaced apart at tlie inner edges PI'O'. viding an openin encircling the mold through which the discharged material may pass into the receiver. v

17. In a centrifugal casting machine, a'

for maintaining the mold -an.a-ngle to the vertical; v v 19. In a centrifugal casting machine, a. 'revoluble mold member having an open up* per end into which molten material maybe V support; I th mold member of cylindrical form having an open upper end, a revoluble housing supporting the mold, a cover for the. mold having a central aperture less in'dian'ieter than 1 the open end of the mold determining the thickness of the wall of the material remainmg in the mold during the casting operation,- thc excess material being discharged. through the aperture of-the cover, and a} receiver ositi'oncd about the mold andcover having an inner circumferential opening through which excess material-may pass.

18. In a centrifugal casting machine, a hollow mold member open at the upper end for introduction of molten metal, a revoluble housing supporting the said mold memher having an open end forvintroduction or removal of the mold, and a cover member adapted to be lacedover the open end'of the mold and ousing retaining the mold therein", said cover having a central, aper-v ture less than the diameter of the open end of the mold and defining the thickness of material retained in the mold, and means with ItS' axis at introduced and through which an excess of material may bedischarged by centrifugal force, a receiver member of cylindrical form positioned about the mold and having a central opening of greater diameter than the mold, said receiver. having an inner peripheral opening through which material discharged from the mold may flow, said receiver member being of greater capacity than the mold and being adapted to retain the material discharged thereinto, and .a

cover membersupportedby the receiver and covering the mold.

20. In a centrifugal casting machine, a cylindrical mold member open at one end only, a. revoluble housing supporting the mold member into which the mold may be introduced or removed, a cover member extendinglover the open end of the mold to retain the same in place, said cover having a central aperture less in diameter than the diameter of the mold means for supporting the housing with the axis of the mold member lat any one of various angles to the-vertica v 21. In a centrifugal castin machine, a hollow mold member, a. revoluble housing supporting the mold member and into which position to retain the mold inthe housin 7 and centrifugally actuated means for holding the cover in place, the cover having a central aperture through which molten metal may be introduced into the mold means for housing with the axis of the "the member may be introduced or removed, fieation.

'and a cover removable member adapted to mold member at any oneof various angles to the vertical.

- 22. In a centrifugal casting machine a hollow mold member, a revoluble housing supporting the mold member and into which be introduced into the mold means for holding the axis of the mold member at an angle to the vertical. e

In testimony whereof I sign this speei retain the mold in place and having a central JAMES'W. GOBURN.

aperture through which molten metal may 

